Tube expander



April 25, 1939. G. A. GEYER ,TUBE EXPANDER Filed March 19,

m mm INVENTOR GEORGEAGEYER BY 2 I ATTOR Fatented Apr. 25, 1939 casters (Granted under the at of March a, 1883, as amended-April so, 1928; 310 o. G. 757) This invention relates toa tube expander, and has for an object to provide a tube expander especially adapted for expanding the ends of tubes when fastening them to boiler drums or 5 sheets in making boilers, as well as fastening condenser tubes to their drums r sheets. I

A further object of this invention is to provide a device for expanding tubes and at the same time for flaring out the ends in the same oper- 10 ation.

A further object of this invention is to provide an expander in the form of a ball drift which will produce a highly burnished surface that will prolong the life of the tube through eliminating 15 the flaking and thinning out that is often produced with the conventional roller type tube expanders.

A further object of this invention is to. provide a ball drift expander which may be used in 20 conjunction with a hydraulic press or arbor ,press as well as with apneumatic hammer or other suitable source of intermittent or continuous pressure. 1

-A further object of this invention is to provide 25 a ball drift which may be easily disengaged by an initial retractive motion to disengage it and 'permitit to be withdrawn without any effort. A further object of this invention is to provide a ball drift which is conical shaped and split 30 diagonally tothereb'y eliminate scarring the tube during the expanding operation, and which is so mounted as to expand itself during the expanding operation, and which will contract to permit it to be withdrawn without effort.

With the foregoing and other objects in view, the invention consists in the construction, combination and arrangement of parts hereinafter described and illustrated in the drawing, in which: V v 40 Fig. l is a. partly sectional and partly elevational view of the expander form of this invention in operation on a boiler tube.

Fig. 2 is an elevational view of the ball drift? 56:1-pneumatic hammer or other power device pro- '.vided with an,,adapter ii for securing a tool ishankfl thereto, the tool shank ifi'terminating ,a threaded, end 43. Secured to this shank {end Blfisthe ball-drift holder i6 consisting of a necting by a 'shoulder I! to a frusto-conical taper portion I8, the taper portion l8 having a shoulder 23 and neck 24 connecting it to a male threaded end 29 for receiving a ball'holding nut- IS, the threaded end 29 and nut l9 having juxtaposed dowel holes when the nut is screwed against shoulder 23, whereby dowel 20 may be inserted to prevent the nut l9 from unthreading.

On the frusto-conical or taper portion i8 is placed the internally conical externally spherical 10 ball drift H, which is slit diagonally as at 26, the inside of the bail being shaped to correspond with the shape of the taper portion [8.

In operation, the ball drift is inserted into a boiler tube 25 and the pneumatic hammer or power source is operated to force the tool shank into the tube. This causes the ball drift 2| to expand along its diagonal split 26 and travel up the taper portion [8 until it abuts the shoulder stop 57. Further operation then causes the ball drift ft to expand the tube from the size at 28 to the size at 21. The surface of the ball drift being highly polished, the resulting inner surface at 2? is correspondingly smooth and polished as a result. If the tube 25 is being inserted 25 into a boiler, its end is placed in the appropriate aperture in the boiler drum, and then the ball drift is passed therethrough, expanding the tube into a tight, leakproof fit with the sides of the aperture of the boiler drum or sheet. To remove 30 the ball drift, the shank is slightly withdrawn, causing the ball drift to travel down its taper l8 and contact, permitting easy withdrawal.

In Fig. 3 is shown an application of this invention ,to a condenser tube and sheet, in further combination with a device for flaring the end of the tube in the sheet. The parts in this flgure which are identical with those-of the first form bear the identical reference numerals. This flaring and ball drift tool 30 has along body portion 3f connecting the female threaded end I5 to its shoulder 91. The body portion 3| is provided with a smoothly curved wedge portion 32 at its upper end connecting it 'to' the female end IS, the distance between the maximum diameter of the ball drift 2! and the wedge portion 32 being substantially equal to the thickness of the condenser sheet 33.

" Then, as-the ball drift and flaring tool 30 is as at 35 against the outside of the condenser sheet 33.

Other modifications and changes in the proportions and arrangements of the parts may be made by those skilled in the art without departing from the nature of the invention, within the scope of what is hereinafter claimed.

The invention described herein may be manufactured and used by or vi'or the Government 01' the United States 01' America for governmental purposes without the payment of any royalties thereon or therefor.

Having thus set forth and disclosed the nature of this invention, what is claimed is;

said spherical member may contract to permit 10 easy removal i GEORGE A. GEYER; 

